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Date: Fri, 11 Nov 2022 16:21:45 -0800
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Subject: Re: [PATCH v2 02/12] x86/ioapic: Gate decrypted mapping on
 cc_platform_has() attribute
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To: Michael Kelley <mikelley@microsoft.com>, hpa@zytor.com,
 kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org,
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References: <1668147701-4583-1-git-send-email-mikelley@microsoft.com>
 <1668147701-4583-3-git-send-email-mikelley@microsoft.com>
From: Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <1668147701-4583-3-git-send-email-mikelley@microsoft.com>
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On 11/10/22 22:21, Michael Kelley wrote:
>  	 * Ensure fixmaps for IOAPIC MMIO respect memory encryption pgprot
>  	 * bits, just like normal ioremap():
>  	 */
> -	flags = pgprot_decrypted(flags);
> +	if (!cc_platform_has(CC_ATTR_HAS_PARAVISOR))
> +		flags = pgprot_decrypted(flags);

This begs the question whether *all* paravisors will want to avoid a
decrypted ioapic mapping.  Is this _fundamental_ to paravisors, or it is
an implementation detail of this _individual_ paravisor?